From: Russell King <rmk+kernel@arm.linux.org.uk>
Subject: [PATCH 01/30] cpuidle: mvebu: indicate failure to enter deeper sleep
 states
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The cpuidle ->enter method expects the return value to be the sleep
state we entered.  Returning negative numbers or other codes is not
permissible since coupled CPU idle was merged.

At least some of the mvebu_v7_cpu_suspend() implementations return the
value from cpu_suspend(), which returns zero if the CPU vectors back
into the kernel via cpu_resume() (the success case), or the non-zero
return value of the suspend actor, or one (failure cases).

We do not want to be returning the failure case value back to CPU idle
as that indicates that we successfully entered one of the deeper idle
states.  Always return zero instead, indicating that we slept for the
shortest amount of time.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
 drivers/cpuidle/cpuidle-mvebu-v7.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/cpuidle/cpuidle-mvebu-v7.c b/drivers/cpuidle/cpuidle-mvebu-v7.c
index 01a856971f05..18ded9e7cb34 100644
--- a/drivers/cpuidle/cpuidle-mvebu-v7.c
+++ b/drivers/cpuidle/cpuidle-mvebu-v7.c
@@ -39,8 +39,12 @@ static int mvebu_v7_enter_idle(struct cpuidle_device *dev,
 	ret = mvebu_v7_cpu_suspend(deepidle);
 	cpu_pm_exit();
 
+	/*
+	 * If we failed to enter the desired state, indicate that we
+	 * slept lightly.
+	 */
 	if (ret)
-		return ret;
+		return 0;
 
 	return index;
 }
-- 
2.1.0

